Anybody know sample code on how to program MX25L1606 NOR flash? I work on my u-boot code but hit a problem here, the u-boot/driver/mtd/spi/macronix.c does not have support code for this chip. I googled cannot any reference on this either.

There is sample code to get you started. Also there is the document on migrating to 1606E which should be helpful, if you have some working code for the 1605D. I believe the FreeBSD people have some MX25L support...